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This time last year, we were up to our knees in muskeg. Wayne was finishing off a book on the
boreal forest and he wanted some close-up shots of labrador tea and other plants that grow
there. I can't say I was thrilled about the idea. One early traveler described muskeg as "a
treacherous, sucking, ill-smelling bog of peaty muck, spongy sphagnum moss and standing
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This western skunk cabbage was photographed in south-central British Columbia with a Nikkor 600mm and a 27.5mm extension tube.
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water." In fact, the opinion of many is that muskeg "just lies there, smeared across Canada like
a leprosy...In summer, it's a rotting mushland of blackflies and mosquitoes, and the odor is akin
to backed-up septic tanks." Indeed, for the novice, muskeg can be a terrifying maze of
tamarack and spindly spruce, and nothing more than an inhospitable wetland. But Wayne
convinced me that muskeg can also be a landscape of inspiring beauty and rich biological
wealth. Here, you can discover puzzling carnivorous plants, delicate showy orchids and
secretive nesting hawk owls. Above the hum of insects, you can hear the bugling duets of
courting sandhill cranes, the primal howl of wolves and the distant siren call of lovesick loons.
Muskeg is not for the meek or timid, but the photographic challenges it poses are filled with
reward. We easily spent five hours mucking in the muskeg, photographing close-ups of the
frost-rimmed leaves of labrador tea, the crimson foliage of shrubby birch, the textured delicacy
of sphagnum moss and the golden needles of autumn tamaracks. Close-up photography
always slows us down, and allows us to rediscover the hidden treasures of Nature.
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We used a Nikkor 800mm and a 27.5mm extension tube to capture this pine grosbeak in northern Alberta. Many songbirds are quite small, and to achieve a tight photograph it's often necessary to use an extension tube no matter how long a lens you use.
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Last month, we began our discussion of close-up photography. If you haven't read that column
yet, we suggest you do, as it will help you to better understand the whole topic. Basically there
are two ways to photograph the miniature world of close-ups. You can use close-up lenses,
also called diopters, or extension tubes. This month we will concentrate on extension tubes.
An extension tube is a simple metal spacer that you mount between the lens and the camera
body. The tube permits whichever lens you use to focus closer than it normally does when it is
mounted directly on the camera. When the size of the extension tube equals the focal length of
the lens (e.g. a 28mm extension tube attached to a 28mm lens), the field of coverage of that
lens becomes 1:1, i.e. life size. You'll recall from our column last month, when you focus most
conventional lenses to their minimum focusing distance, the field of coverage roughly equals an
area the size of a piece of typing paper. With life size, the field of coverage is reduced to the
area inside a 35mm slide (assuming of course you are using 35mm film).
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To capture this sun scorpion we used a Nikkor 200mm macro lens and full TTL flash with the flash compensation set at +1.00.
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Extension tubes come in different sizes. Nikon currently makes an 8mm tube (PK-11), a 14mm
tube (PK-12), and a 27.5mm one (PK-13), as well as the mother of all extension tubes, a
200mm auto bellows (PB-6). Canon also offers an entire range of extension tubes: 15mm (FD-15),
25mm (FD-25), 50mm (FD-50) and a 200mm bellows. All of the extension tubes range in
price from roughly $60.00 to $80.00 each, and the bellows cost around $230.00. Unfortunately,
none of these listed has the necessary electrical circuitry to maintain autofocus in the attached
lens so you must focus manually. Canon, however, does make two additional extension tubes,
the 12mm (EF-12) and the 25mm (EF-25) for their EOS camera series, both of which retain
autofocus capability and cost just a bit more than the non-autofocus extension tubes.
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Many wild animals, such as this unwary Adelie penguin from Antarctica, will let you get very close to them, providing an opportunity to do close-up photographs. To make this photograph we used a Nikkor 200mm macro that gave us enough working distance not to frighten the bird.
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All extension tubes can be stacked together to achieve different amounts of extension. Since
there is no glass in any extension tube there is never the worry that you will degrade the
sharpness of your master lens. There is a down side to everything, however, and the big
disadvantage to using extension tubes, (besides the loss of autofocus in some models) is loss
of light. Since extension tubes distance the lens from the camera body, light must travel farther
to reach the film plane, so more light is needed to produce an image. When you extend a lens
far enough to achieve life size, 1:1, you lose two stops of light. Typically, at such
magnifications, its also customary to use a very small aperture, say f/22 or f/32, to yield
sufficient depth of field. If you are using a slow film such as Fujichrome Velvia (ISO 50) to get
maximum color saturation and fine grain, natural daylight in this situation is just too weak to
illuminate the subject and you must use an electronic flash.
The real beauty of extension tubes is that they can be used with any lens you own. Recall from
last month that close-up lenses, which are attached like a filter to the front of a lens, can only be
used on lenses whose front element is smaller than 77mm in diameter, which is the largest
close-up lens made by any camera manufacturer. For us, this means that we can't use close-up
lenses on many of our large telephotos, including our 300mm f/4, 500mm f/4 or our 800mm
f/5.6. But we can use extension tubes with all of these lenses, and with great success. For
example, the minimum focusing distance on our Nikon 800mm is 26 feet. If we add a PK-13
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A 60mm macro allowed us to capture this jewel lichen on a backpacking trip in the Canadian High Arctic.
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(27.5mm extension tube), the minimum focusing distance drops to 21.5 feet. This may not
sound like much of an improvement to you, but the closer focusing capability greatly improves
the composition, especially when we are photographing small songbirds, such as warblers and
sparrows. We also commonly use large telephoto lenses with extension tubes to photograph
flowers because the narrow angle of view of such large lenses often yields an attractive clean
background.
We've now talked about close-up lenses and extension tubes, but what about macro lenses?
Basically, a macro lens is simply a lens with built in extension tubes that focus all the way down
to life size. Both Nikon and Canon produce macro lenses in different focal lengths, but before
you buy one you should consider the pros and cons of each. Here are some details to consider:
Nikon Macro Lenses
- 60mm f/2.8, minimum focusing distance = 9 in, weight = 1 lb, approx. cost = $380.00
- 105mm f/2.8, minimum focusing distance = 12 in, weight 1.25 lb, approx. cost, = $650.00
- 200 mm f/4, minimum focusing distance = 19 in, weight = 2.5 lb, approx. cost = $1325.00
Canon Macro Lenses
- 50mm f/2.5, minimum focusing distance = 7 in, weight = 10 oz, approx. cost = $340.00
- 100mm f/2.8, minimum focusing distance = 10 in, weight = 1.5 lb, approx. cost = $570.00
- 180mm f/3.5, minimum focusing distance = 20 in, weight = 2.4 lb, approx. cost = $1400.00
How do you decide which macro to own? Let's assume that price is not a consideration, that
leaves two factors to consider: weight and minimum focusing distance. We use the Nikkor
60mm macro primarily for backpacking and hiking when weight is a critical issue. This small
macro lens is fairly light, but the minimum focusing distance is quite close and at such a short
distance, insects and frogs are likely to be frightened away. As a result, this macro works best
on wildflowers and other close-up subjects that lack a beating heart. Our favorite macro lens is
the Micro-Nikkor 200mm. Although it is two and a half times heavier than the 60mm macro, its
minimum working distance is 19 inches, a comfortable distance for skittish critters that are apt to
flutter, scuttle, slither or hop away. The other feature of the 200mm macro that we love is the
tripod collar on the lens. The collar makes it easy to rotate the lens from a horizontal position to
a vertical one.
In the end, extension tubes, macro lenses and close-up lenses each have their own advantages
and disadvantages. We use all of them on a regular basis. Our best advice is to start out
simply and cheaply. Buy a single close-up attachment of some sort, either an extension tube or
a close-up lens, and then experiment with it in the field. You will soon discover its limitations
and capabilities, and that will help you to decide whether you should invest in an expensive
macro lens. Close-up photography is one of the most relaxing kinds of nature photography we
do. Try it some time after you've had a tense day at home or at the office. It works wonders.
Questions and Answers
Wayne Lynch and Aubrey Lang will occasionally answer
readers' questions in their bi-monthly column. They can be contacted via e-mail
at
this address: lynchandlang@photosafaris.com.
Due to the anticipated volume of
inquiries Wayne and Aubrey cannot answer questions individually.
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